#include <bits/stdc++.h>
using namespace std;

#define ll long long

const int MAXN = 505;

int dx[4] = {0, 0, -1, 1};
int dy[4] = {1, -1, 0, 0};

int vis[MAXN][MAXN];

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);

	int n, m; cin >> n >> m;
	int cnt = 0;
	int found = 1;
	bool possible = 0;
	queue<pair<int,int>> q;
	q.emplace(1,1);
	while (cnt < 2999 && !q.empty() && found < m) {
		auto cur = q.front();
		int cx = cur.first;
		int cy = cur.second;
		q.pop();
		if (vis[cx][cy] != 0) continue;
		cout << cx << " " << cy << endl;
		string s; cin >> s;
		if (s[0] == 'B') {
			vis[cx][cy] = 1;
			found++;
			if ((cx == n && cy == n) || (cx == n-1 && cy == n) || (cx == n && cy == n-1)) {
				possible=1;
				break;
			}
		} else if (s[0] == 'W') {
			vis[cx][cy] = 2;
			continue;
		} else {
			cout << "ERR" << endl;
			return 0;
		}
		cnt++;
		for (int d = 0; d < 4; ++d) {
			int nx = cx + dx[d];
			int ny = cy + dy[d];
			if (nx <= n && nx >= 1 && ny <= n && ny >= 1 && vis[nx][ny] == 0) {
				q.emplace(nx, ny);
			}
		}
	}

	if (possible) {
		cout << "Yes" << endl;
	} else {
		cout << "No\n";
	}


	return 0;
}